Magnetic heads for perpendicular magnetic recording have recently been proposed in order to increase the recording density and capacity of a magnetic disk drive or reduce its size. In one such magnetic head, a recording head comprises a main pole configured to produce a perpendicular magnetic field, trailing shield, leading shield, and coil. The trailing shield is located on the trailing side of the main pole with a write gap therebetween and configured to close a magnetic path that leads to a magnetic disk. The leading shield is located on the leading side of the main pole. The coil serves to pass magnetic flux through the main pole. Further, a high-frequency assisted head is proposed in which a high-frequency oscillator is provided between the main pole and a medium-side end portion of the trailing shield and an electric current is applied to the high-frequency oscillator through the main pole and trailing shield.
According to the magnetic recording head described above, an effective recording magnetic field of the head is enhanced as the high-frequency oscillator is oscillated, whereby the magnetization reversal of a recording layer of a recording medium is improved. When the head is used for high-bandwidth transfer, however, there is a problem that a magnetic field response in a magnetic core cannot be satisfactorily followed, so that the error rate is degraded.